It is estimated that over ten million vehicles in the United States are equipped with trailer hitches—almost all trucks, recreational vehicles and pickups are so equipped. Also many cars are furnished with trailer hitches to pull travel trailers and small utility trailers. When considering the world, an estimate of over fifty million vehicles having trailer hitches would seem reasonable.
Trailer hitches have been designed to permit trailers to be quickly and conveniently attached and detached. But by designing trailer hitches to be easily used, trailers and attached wheeled carriers can be easily detached and stolen easily by removing the ball and locking nut of the hitch.
Therefore, it is clear that a simple, yet effective means for securing trailers to trailer hitches is of significant utility and value to owners of trailers and hitches.